Fig. 4. Structure of the genomic locus of the class I Beats. Shown are the locations and direction of transcription of the class I Beats at chromosome band 35 on 2L; distal regions are to the left. Each of the genomic loci of the Beats appears to be roughly as large (15-20 kb) and complex as this. Intervening genes are omitted. Chromosomal deficiency stocks used in this study are depicted below. The breakpoints for Df(2L)RA5 and Df(2L)TE35D-GW11 were mapped originally for this study; the breakpoints for the other Dfs listed are from Fambrough and Goodman (Fambrough and Goodman, 1996).